Magnifying stereoscope



June 9, 1959 E. 1|.. RABBEN MAGNIFYING STEREOSCOPE Filed March 25, 1957 51% T/aA/HRY QFIELE:

INVENTOR.

2L/s L. @neef/V BVMW-ZM Arran/f Y MAGNIFY IN G STEREOSCOPE 'Application March 25,V 1.957, Serial No. 648,392 2 Claims. (Cl. 88-29) This invention relates to stereoscopes, and more particularly to a magnifying stereoscope especially useful in Photogrammetry.

` A main object of the invention is to provide a novel and improved stereoscope which is simple in construction, which is` easy to use, and which is arranged so that it provides either of two different degrees of magnification of stereoscopic pictures employed therewith.

A further object of the invention is to provide an improved magnifying stereoscope which is inexpensive to manufacture, which is durable in construction, which is compact in size, and which is arranged so that the magnification thereof may be changed by a very simple manipulation.

Further objects and advantages of the invention will become apparent from the following description and claims, and from the accompanying drawings, wherein:

Figure 1 is a transverse vertical cross-sectional View taken through a stereoscope constructed in accordance with the present invention.

Figure 2 is a vertical cross-sectional view taken substantially on the line 2 2 of Figure 1.

Figure 3 is a top plan view of the stereoscope of Figures l and 2.

Figure 4 is a diagrammatic perspective View showing the relative positions of the optical components of the stereoscope of Figures 1 to 3.

Figure 5 is an enlarged vertical cross-sectional view taken on line 5 5 of Figure 3.

Referring to the drawings, 11 generally designates a stereoscope of adjustable magnification constructed in accordance with this invention. The stereoscope 11 comprises a generally rectangular housing 12 open at its bottom and provided with four vertically depending legs 13 rigidly secured to its front and rear walls adjacent its corne-rs, so that the housing may be supported over a pair of side-by-side stereoscopic pictures 14, 14, which are illuminated by any suitable outside source of light.

Housing 12 has a downwardly and forwardly sloping forward top wall portion 15 and a downwardly and rearwardly sloping rear top wall portion 16. Mounted in the forward top wall portion 15 are the laterally spaced, achromatic lens units 17, 17, which are spaced to dene eyepiece elements, the front wall of the housing being suitably recessed between the lens units, as shown at 18, to facilitate the close approach of the users eyes to the respective lens units.

Lens units 17, 17 are spaced apart by a distance substantally equal to the spacing between a persons eyes.

Secured rigidly to the inside surface of the sloping rear top wall portion 16 are a pair of downwardly facing concave mirrors 19, 19, spaced apart and arranged to receive light rays from the respective side-byside stereoscopic pictures 14, 14 when the device is positioned over the pictures as above described. The mirrors 19 are secured firmly against the bottom surface of the top wall portion 16, and the angle of inclination of said top wall portion is suicient so that the light rays thus ICC received will be reflected from the mirrors 19 toward a pair of additional mirror units 20, 2t) arranged horizontally in the housing in a manner presently to be described, and so that thelight rays will be reflected from said horizontal mirror units toward the respective lens units 17, 17.

Mirrors 19 are preferably concave so as to provide a predetermined amount of magnification of the images dened by the light rays received thereby, but may be merely plane mirrors if so desired` Each horizontal mirror unit 20 .comprises a suitable supporting ringk 21 in which is secured a double-faced mirror element 22 having a plane mirror 23 on one face thereof and a concave mirror 24-on the other face thereof. The mirror units are rigidly secured to respective yaxially aligned shaft segments 25, 26 and 27, as shown in Figure 2, the outer shaft segments 27 and 25 -being journalled respectivelyin the side walls 28 and 29 of housing 12. The shaft segments are of suitable length to support the mirror units in positions to respectively reilect the` light rays from the fixed mirrors 19, 19 to the respective eyepiece lens units 17, 17 when the mirror units are in horizontal positions, for example, as shown in Figures l and 2.

Shaft segment 25 has an outwardly projecting end portion 30 on which is rigidly secured a circular knob 31, employed to manually rotate the mirror units 20, 20 .when the magnification of the device is to be changed. Knob 31 is provided ou its inner face with a springpressed ball detent 32 selectively engageable in diametricallyopposite locking recesses 33v and 34 formed in side wall 29, so that the mirror units may be yieldably locked in either of two horizontal positions, namely, with their plane mirror surfaces uppermost, as shown in Figures l and 2, or with their concave mirror surfaces 24 uppermost.

As will be readily apparent, a first degree of magnification of the stereoscopic images will be obtained when the plane mirror surfaces 23 are uppermost. To obtain a higher degree of magnification, the knob 31 is rotated degrees from the position thereof shown in Figure 2, whereby the concave mirror surfaces 24, 24 will be uppermost and will provide the desired higher magnification.

If so desired, both surfaces of the respective mirror units 20, 20 may be concave or otherwise suitable contoured, to provide desired different degrees of magnification when the mirror units are reversed.

The supporting legs 13 are provided at their lower end portions with slidable height-adjusting sleeves 35, so that the height of the housing 12 may be adjusted for proper focussing when the mirror units 20, 20 are reversed. The sleeves 35 are provided with yieldable ball detent members 36 which extend into vertical grooves 37 formed in the legs 13 and which are selectively engageable in respective locking recesses 38 and 39 provided in the lower and upper end portions of the grooves to yieldably secure the sleeves in their respective adjusted positions on the legs.

While a specific embodiment of a stereoscope of adjusta-ble magnification has been disclosed in the foregoing description, it will Ibe understood that various modifications within the spirit of the invention may occur to those skilled in the art. Therefore it is intended that no limitations be placed on the invention except as dened by the scope of the appended claims.

What is claimed is:

1. A stereoscope comprising a housing open at its bottom and having opposite vertical side walls and a top wall comprising an upwardly and rearwardly inclined front portion and a downwardly and rearwardly inclined rear portion, means to adjustably support said housing in an elevated position on a horizontal supporting surface over a pair of side-by-side stereoscopic pictures, horizontal shaft means rotatably mounted in said side walls on an axis parallel to said inclined top wall, portions, a pair of stereoscopic eyepieceelements mounted in said front portion, a pair of identical double-faced mirrors mounted on said shaft means, a pair of reflecting mirrors secured to the inside surface of said rear top wall portion, said mirrors being formed and arranged to reflect the images of the respective stereoscopic pictures ,to the respective eyepiece elements when said double-faced mirrors are in substantially horizontal posi tions, the opposite faces of said double-faced mirrors having different magnifying properties, an operating element externally secured on .said shaft means adjacent one of said vertical side walls, said one of the side walls being formed with respective locking recesses at diametrically opposite locations relative to said shaft means, and a yieldable locking element on said operating element engageable in one or the other of said locking recesses when said double-faced mirrors are in horizontal positions.

2. A stereoscope comprising a housing open at its bottom and having opposite vertical side Walls and a top wall comprising an upwardly and rearwardly inclined front portion and a downwardly and rearwardly inclined rear portion, a plurality of spaced vertical legs secured to said housing to support said housing in an elevated position on a horizontal supporting surface over a pair of side-by-side stereoscopic pictures, horizontal shaft means rotatably mounted in said side walls on an axis parallel to said inclined top wall portions, a pair of stereoscopic eyepiece elements mounted in said front f portion, a pail of identical double-faced mirrors mounted on said shaft means, a pair of reflecting mirrors secured to the inside surface of said rear portion, said mirrors being formed and arranged to reect the images of the respective stereoscopic pictu-res to the respective eyepiece elements when said double-faced mirrors are in substantially horizontal positions, the opposite faces of said double-faced mirrors having different magnifying properties, an operating element externally secured on said shaft means adjacent one of said vertical side Walls, said one of the side walls being formed with respective locking recesses at diametrically opposite locations relative to said shaft means, a yieldable locking element on said operating element engageable in one or the other of said locking recesses when said double-faced mirrors are in horizontal positions, Irespective sleeve members slidably engaged on and depending from said legs, and yieldable detent elements carried by said sleeve members, the lower end portions of said legs being each formed with a pair of vertically spaced locking -recesses in which said detent elements are lockingly receivable, whereby said sleeve elements are adapted to support said housing in either of two elevated positions on the supporting surface.`

References Cited in the le of this patent UNITED STATES PATENTS 1,350,042 Stealy Aug. 17, 1920 2,136,486 Blondin Nov. 15, 1938 2,363,427 Langberg Nov. 21, 1944 2,426,888 Langberg Sept. 2, 1947 2,503,342 Knight Apr. 11, 1950 FOREIGN PATENTS 210,472 Great Britain Feb. 5, 1924 718,550 Great Britain Nov. 17, 1954 

